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Less than 2 weeks after Valentine's Day, the New York Times ran a front page exposé on the strong links between job loss from manufacturing plant closures and heart attacks among those dealing with sudden unemployment ("For Workers at Closing Plant, Ordeal Included Heart Attacks" http://query.nytimes.com/gst/fullpage.html?res=950CEEDC103FF936A15751C0…) To experts in the field of occupational and environmental health this link is hardly a revelation, but one need not rely on technical expertise for confirmation. Common wisdom draws similar conclusions from the wider human experience - one is reminded of the answer to the folk song riddle, what can cry without tears? (A heart...)
It is well known that not only psychological stress, but also physical stress and the physiological stress on system from selected toxic substances can each independently increase cardiovascular disease risk. The workplace, unfortunately, is sometimes a laboratory where all three types of stressors are tested out simultaneously.
After war, natural disaster, and life-threatening illness, losing one's livelihood is arguably one of the most severe sources of stress one is likely to encounter. And this is more than simply monetary. The newly appointed head of the Federal Occupational Safety and Health Administration (OSHA), Dr. David Michaels, examined this very question in an innovative study he carried out more than 20 years ago. He analyzed the incidence of heart disease among a special group of skilled blue collar workers: printers whose craft work was no longer needed, but who contractually maintained their previous pay even though they came to work everyday with virtually nothing to do. Without useful employment, even though with salary protection, many of these workers became ill. Michaels subtitled his thesis, "What becomes of the broken-hearted?"
Two workplace physical hazards in particular are noteworthy for their potential cardiovascular effects: noise and vibration. Excess noise exposure on the job is ubiquitous. This is not an issue limited to factory manufacturing - the construction, agriculture, and transportation industrial sectors are all problem-ridden. Vibration exposure occurs through the use of power tools and, even more widely, through operating large equipment and driving vehicles. Often the two exposures go together and, although the biological mechanisms are unclear, both have been linked consistently to high blood pressure.
A number of toxic substances can stress the cardiovascular system. One of the most important is carbon monoxide. At high levels, carbon monoxide is an acute poison by virtue of oxygen deprivation. At lower levels, with long-term exposure, it appears to impart significant risk to the heart, in particular to persons with pre-existing disease from other causes. Carbon monoxide is a major byproduct of combustion engines, although there are many other sources of exposure as well.
So it's not too hard to come with a classic triple threat to the heart in a work-related scenario: a long-haul truck driver newly out of work. According to the data recently released by the U.S. Bureau of Labor Statistics (http://www.bls.gov/news.release/pdf/empsit.pdf) on Valentines Day, February 2010 there were almost 1.4 million unemployed persons in transportation and material moving occupations - 15% of that workforce. That's a lot of crying without tears.
